Method of cleaning mica and similar material



Oct. 24, 1939. c Twoo 2,177,358

METHOD OF CLEANING MICA AND SIMILAR MATERIAL Filed July 17, 1937ATTORNEY Patented Oct. 24, 191 39 UNITED STATES PATENT OFFICE FrancisClarke Atwood,

to Atlantic Research Associates,

Newton, Mass., assignor Inc., Wilmington, Del., a corporation ofDelaware Application July 17, 1937, Serial No. 154,132

4 Claims.

With this general object in view, and such others as may hereinafterappear, the invention consists in the method of cleaning and in the 15cleaning apparatus hereinafter described and particularly defined in theclaims at the end of this specification.

In the drawing I have illustrated a suflicient portion of a cleaningapparatus embodying the 2 invention and for practicing the presentmethod,

as will enable the invention to be understood,

wherein Fig. 1 is a view partly in section and partly in plan of thepreferred form of cleaning apparatus; and Fig. 2 is a sectional view onthe line 2-2 of Fig. 1.

The present invention finds particular use in dry cleaning mica andsimilar materials and for convenience of description will be describedin connection with the dry cleaning of mica, and 30 in accordancetherewith the mica is subjected to successive blows in a manner such asto effect the crushing of the quartz, sand, dirt, or other brittlematerial, while permitting the flakes or laminae of mica to flex withoutinjury, thus reducing the dirt or foreign matter to a finely dividedstate, and at the same time dislodging the same from adherence to themica flakes or laminae without substantially effecting the mica flakesor particles. In the preferred and illustrated form of dry cleaningapparatus, the desired action is secured by causing the mica flakes topass between successive rows of concentrically arranged impingingmembers such as pins, which are rotated to impart blows to the micawhile permitting the mica to flex around the pins and be gradually movedoutwardly through the same by centrifugal force. The apparatus alsopreferably embodies a separating device for pneumatically separating thefinely divided foreign matter from the much larger and cleaned micaflakes after the foregoing action has taken place.

Referring now to the drawing, the illustrated cleaning apparatuscomprises an operating chamber formed by an upper plate III, a lowerplate l2 spaced therefrom, and a circular plate I 4 forming the sidewall of the chamber and to which the upper and lower plates l0, l2 arebolted, as shown. The upper plate In is provided with an axiallyarranged inlet opening l6 into which a hopper I8 is fitted to deliverthe mica or other material to be cleaned into the operating chamber. Theoperating chamber has disposed within the lower portion thereof arotatable plate 20 having a series of impinging members 22 herein shownas comprising pins upstanding therefrom 10 and arranged to extend nearlyto the upper plate It] forming the top of the chamber. The upper plateI0 is provided with a series of similar impinging members 24 arranged toproject downwardly from the plate and the two sets of impinging members22, 24 are arranged concentrically with the axis of rotation of theplate but at different radial distances so that the rows of stationaryand movable pins 22, 24 are alternately disposed.

Provision is made for rotating the plate 20 and its pins 22 atrelatively high speed, and as herein shown the plate 20 is mounted uponthe upper end of a vertical shaft 28 journalled in suitable bearings 30supported in the frame 32, and the power from any suitable source may betransmitted through the driving pulley 34, shaft 36 and beveled gears38, 39 on the ends of the shafts 36 and 28 respectively. The side walll4 of the operating chamber is provided with a discharge opening 40, andas herein shown the opening 40 is connected by a conduit 42 tangentiallydisposed with respect to the rotatable plate 20 and through which themica, after having been subjected to the action of the pins 22, 24, isthrown by centrifugal force into a pneumatic separator 44 of any usualor preferred design and which as herein shown comprises a separatingchamber 46 into which the larger and finer particles of the materialsuch as mica and the finely divided dirt are introduced and from whichthe fine particles of dirt and other foreign matter may be withdrawnthrough the pipe or conduit 48 by a fan 49 and discharged into a dustcollecting bag, not shown, within the chamber 50. The clean mica orother material is discharged through a discharge chute 52 from the lowerend of the chamber 46.

From an inspection of Figs. 1 and 2 it will be observed that the pins orimpinging members 22, 24 are arranged in rows radiating from the centerof the operating chamber and are arranged so that a movable pin 22alternates with a stationary pin 24 and the pins are arrangedsufllciently close together so as to exert a crushing action on u thequartz, sand or other dirt particles while permitting the flexible micaflakes to pass substantially uninjured between the pins during themovement of the flakes outwardly to the periphery of the operatingchamber. As a result it will be observed that the present apparatusexerts not only a flexing and beating action upon the mica flakes butalso a crushing action upon the larger particles of quartz, sand orother dirt particles, thus facilitating the ultimate operation of thefinely divided dirt and much larger mica flakes.

In the operation of the apparatus, the mica to be cleaned is introducedinto the hopper l8 where it is delivered by gravity into the operatingchamber at a central or axial point therein so that as the plate 20 isrevolved at relatively high speeds, such for example as from six toeight hundred revolutions per minute, the mica flakes are caused to moveoutwardly in radial directions between the successive rows of themovable and stationary pins or impinging members 22, 2.

.As a result of the movement of the mica by the centrifugal forceimparted thereto by the rotating plate 20, and the pins 22 carriedthereby, the mica flakes are subjected to a flexing action as they windtheir way in and out between the pins, and at the same time the flakesare subjected to impulses or blows from the moving pins 22. As each ofthe mica flakes passes a stationary pin it snaps and the combined effectof the flexing, the sudden beating of he pins against the flakes,together with the snapping action as the flakes leave the pins in theirmovement outwardly, causes all or substantially all of the dirt andforeign matter to be dislodged from the mica flakes, so that when thematerial reaches the periphery of the operating chamber and is thrownoutwardly through the discharge conduit l2 into the separator as abovedescribed, the fine material including the dust and dirt is readilyseparated from the larger flakes of mica and the latter are dischargedin a clean condition through the discharge outlet 52. In this manner theseparation of the dirt and foreign matter from the flakes of the mica orother similar material may be accomplished in a simple, economical andhighly eflicient manner.

While the preferred apparatus for cleaning mica and similar material hasbeen herein illustrated and described, it will be understood that theinvention may be embodied in other forms within the scope of thefollowing claims.

This application is a continuation in part oi my application Serial No.90,960, filed July 16, 1936.

Having thus described the invention, what is claimed is:

1. The method of cleaning mica and similar material which consists insubjecting the mica to be cleaned to a combined flexing and beatingaction to mechanically dislodge the dirt and foreign matter from thelaminae thereof by passing the mica between closely adjacent relativelymoving overlapping pins so spaced and operating at a speed to accomplishsaid flexing and beating action and mechanical dislodging of dirt andforeign matter.

2. The method of cleaning mica and similar material which consists insubjecting the mica to be cleaned to a combined flexing and beatingaction to mechanically dislodge the dirt and foreign matter from thelaminae thereof by passing the mica between closely adjacent relativelymoving overlapping pins so spaced and operating at a speed to accomplishsaid flexing and beating action and mechanical dislodging of dirt andforeign matter, and subsequently separating the flnely divided dirt andforeign matter from the larger mica flakes,

3. The method of treating mica and similar laminated material to removedirt and other foreign impurities therefrom, which comprises passing themica between relatively smooth members moving relative to each other atsuch a speed and so spaced as to engage the laminae at spaced points andproduce essentially a snapping and flexing of the laminae accompanied bya grinding of the larger particles of the impurities and a dislodging ofthe impurities from the laminae.

4. The method of cleaning and separating mica and similar laminatedmaterials from dirt and other foreign impurities which comprises passingthe mica between relatively smooth members moving relative to each otherat a speed and so spaced as to engage the laminae at spaced points andproduce essentially a snapping and flexing of the laminae accompanied bya grinding of the larger particles of the impurities and a dislodging ofthe impurities from the laminae, and pneumatically separating thecleaned mica from the 50 impurities.

FRANCIS CLARKE ATWOOD.

